Hydraulic axial vane pump or motor



April 5, 1949. w. R. TUCKER ETAL HYDRAULIC AXIAL VAflE PUMP OR MOTOR Filed March 11, 1944 2 Sheets-Sheet 1 IN V ENTOR 5 .IUCKER, DIETERICH T ijmmagww ATTORNEYS April 9 9 w. R.- TUCKER ET AL 2,466,623

HYDRAULIC AXIAL VANE PUMP OR MOTOR Filed March 11, 1944 2 Sheets-Sheet 2 lNVENTQR WARREN R. Tucrm JJMLJJ 7 ATTORNEYS Patented Apr. 5, 1949 HYDRAULIC AXIAL YANE PUMP OB-MOTOR Warren R. Tucker and Robert W. Dieterich,

Dayton, Ohio, minors to H-P-M Development Corporation, Mount Gilead, Ohio, a cor poration of Delaware Application March 11, 1944, Serial No. 526,078

1 Claim. 1

This invention relates to hydraulic apparatus and, in particular, to rotary hydraulic devices such as pumps or motors. More particular still, this invention relates to vane type hydraulic pumps and motors wherein the vanes are adapted to move axially rather than radially.

In this type hydraulic device it has been found that the friction created by the sliding movement of the vanes over the cam surfaces which actuate them is detrimental to the life of the said cam surfaces and vanes. In the usual type of construction the wear resulting from the frictional engagement of the vanes and the cam surfaces is sufliclent to create drag and wear and inefficiency due to the leakage of the hydraulic fluid between the ends of the worn vanes and cam surfaces.

Accordingly, it is a primary object of this invention to provide, in an axial ty-pe vane pump or motor, an improved vane and cam construction whereby excessive wear therebetween is substantially reduced. This and other objects and advantages of the present invention will be more clearly apparent from the following specification taken in connection with the accompanying drawings.

In the drawings:

Figure l is a longitudinal section through a pump or motor constructed according to this invention;'

Figure 2 is a section taken substantially along the line 22 of Figure 1 and looking in the direction of the arrows;

Figure 3 is a perspective view of one of the cam bearing members;

Figure 4 is a perspective view of the ring member which retains the vanes;

2 plurality of rises and falls as generally indicated at I8 in Figure 3. The cam surfaces are so shaped that, as the rotor rotates carrying the vanes with it, the vanes are closely confined therebetween at all times. v

The vanes are retained against radial movement by means of a ring member or cage-Ii The member I9 is adapted snugly to fit over the rib l3 and to engage the cam bearing members l6 and II at the annular recesses 20 and 2|, respectively. By means of the ring member IS. the cam bearing members are accurately located one from the other and the vanes are held against radial'movement. The ring member is provided with an external annular groove 22 which communicates through the passages 23 Withthe space between the rib l3 on the rotor l0 and the face of the cam bearing member Hi. The ring member 19 is also provided with notches 24 located around the inner edge thereof and serving to communicate between the exhaust spaces within the pump or motor and the exhaust port of the apparatus.

The ring member I9 is retained within a main casting member 25 which is internally ribbed as at 26 in order to form a mating surf-ace for the said ring member. The main casting is also provided with the end closure plates 21 and 28, the latter of which is apertured to "accommodate the extension of the shaft H.

The shaft II is fitted with suitable anti-friction bearings such as the ball bearings 29, these v bearings fitting within cooperating recesses in Figure 5 is a developed lay-out indicating the 7 pressure and exhaust areas of the motor or pump,

and Y I Figure 6 is an enlarged view showing more particularly the vane and cam construction of this invention;

Referring to the drawings in detail, ill cates a rotor which is amxed to a shaft II by any suitable means suchas the keys l2. The rotor III is provided midway between its ends with a flange or rib l3 within which is mounted a pluindithe aforementioned closure plates. The bearings or closure plates also serve to maintain the cam bearing members liand I'I in abutting relationship with the cage [9. The assembly is maintained in assembled relation by suitable retainin means. such as the screws 30.

Fluid inlet and outlet means are provided in .the casing 25 at 3| and 32. In case the device is being operated as a motor it is preferable that theport32 be'used as the inlet port and the port 3| as an exhaust port. In case the'device is being operated as a pump, it is preferable that the functions of these ports be unchanged.

Referring now to Figure 4, the locations of the passages 23 and. the notches 24 will be apparrality of vanes It. The vanes H are mounted in slots I5 provided in the rib l3 for that purpose. The vanes H are not movable radially relative to the rotor ill. but are slidable axially thereof.

The vanes [4 are enclosed between a pair of cam bearing members l6 and II, which are provided on their inner or facing surfaces with a cut. Around each side 'of the member iii are arranged two groups of the passages 23 spaced at even intervals, that is, at 180. Spaced at from each group of passages 23 is a notch 24. The notches 24 are, therefore, located altintervals around the member l9.

Referring now to Figure 5, there is shown,

diagrammatically, the arrangement of the P sages 28 and the notches 24 in relation to the cam faces It. In this view the rib l3 ofthe rotor I is developed into a plan view and the cam members l1 and I! are, likewise, developed to occupy the proper position relative to the rib II. The passages 21 andthe notches 24 are likewise indicated in their proper'relation to the rotor and cam surfaces. I

From Figure and Figure 3 it will be seen that the cam surfaces It are each divided into a plurality of hills and valleys, or rises and falls with interposed flat portions. For example, referring to Figure 3, the cam surface is comprised of the rises 35, the falls 36, and the interposed flats 31. Upon reference to Figure 5 it wil be noted that the rises and falls in the cam surface on the member i1, arranged in opposing relationship to the member l6, are so located with reference to the rises and falls on the cam surfaces of the member l8,

that the space therebetween is substantially constant so as thereby closely to, enclose the vanes at all times as the rotor l0 and, therefore, the vanes I 4 move relative to the said cam surfaces. It will, furthermore, be noted from Figure 5 that the cam surfaces are composed of constant rise and fall portions. That is, the vanes are reciprocated' at a uniform rate from one end position to the other as the rotor rotates.

Referring now to Figure 6, the manner in which the vanes are formed to cooperate with the aforementioned cam surfaces will be seen. Each vane comprises a double bevel on each end thereof. the angle of the bevels being identical with the angles of inclination of the rises and falls in the cam surfaces. For example, the vane indicated at A in Figure 6 has the upper right hand bevel thereof incident with, or in contact with the cam surfaces and the lower left hand bevel thereof incident with the cam surface 38. The vane marked B in Figure 6 is just beginning to engage the cam rise 39 with the bevel on the lower right hand portion, and the vane marked C is passing across the flats 31 and is in engagement therewith at the junction point of the beveled end surfaces.

Operation The operation of the device as a motor is indicated in Figure 5 wherein pressure fluid is introduced through the passages 23 and exhaust fluid is conducted away by means of the notches 24. The action of the pressure fluid being introduced through the pasages 23 is to urge the vanes and, therefore, the rotor l0 rightwardly. As the vanes and the rotor move rightwardly the spaces between adjacent vanes move first from under the passages 23, become sealed therefrom in passing across the flat 31 andfinally are exhausted through the notch 24. It will be noted that the space between adjacent vanes is continuously increasing during the time that the space is being filled with pressure fluid, and are continuously decreasing during the time that the space is being exhausted. This is accomplished by the reciprocation of the vanes as they pass across the successive cam surfaces.

- Referring again to Figure 6, it will be noted that i the vane A is subjected to an upward thrust due to the pressure fluid entering from the passages 23. It will also be noted that this thrust is carried between the right hand portion of the bevel on the upper end of the vane A and the cam surface 35. Therefore, the area over which this thrust is distributed is not less than one-half of the end surface of the vane. A similar situsome ation exists in regard to the vane B wherein the thrust is downward and the thrust thereof is carried by the lower right hand bevel of the vane B and the cam surface II.

On the other hand, the vane C, which is passing across the flats 31, is in hydraulic balance, as regard end thrust, since the thrust downwardly thereon from the pressure fluid standing in the upper right hand passages 23 is exactly balanced by an equal and opposite thrust due to the pressure fluid standing in the lower left hand passages 23.

It will be apparent, therefore, that arrangement of constant rise and fall cam surfaces and correspondingly beveled vanes provided in this invention functions substantially to reduce the unit pressure with which the vanes engage the cam surfaces, thereby reduces the wear that takes place therebetween, increases efliciency and promotes longer operating life.

The method of providing surfaces on the vane ends incident with, or in contact with the cam surfaces, likewise reduces fluid leakage from one side of the vane to the other inasmuch as the path by which the fluid travels past the vane is greatly lengthened over that encountered in similar devices wherein the vane engages the cam surface with the line contact.

It will also be apparent that a third surface could be provided on the ends of the vanes for. engaging the flats 31 in order to provide an improved fluid seal at the vane ends, without departing from the spirit of this invention.

Accordingly, it will be understood that we do not desire to be limited by the precise details shown in the drawings, but desire to comprehend such modifications and substitution of equivalents as come within the scope of the claim and the invention.

' We claim:

A fluid pump or motor comprising a casing having a cylindrical bore therethrough and an inlet port and an outlet port, a grooved cylindrical member adapted closely to be received within said bore having the groove thereof in communication with said inlet port, a rotor rotatably mounted within said cylindrical member, a shaft extending through said cylindrical member for rotating said rotor, a plurality of vanes mounted on said. rotor so as to rotate therewith while being axially slidable relative thereto, a pair of opposed cam members on either side of said rotor adapted to abut said cylindrical member, the cam surfaces on said members being located so as exactly to receive said vanes therebetween, a pair of closure members secured to either end of said casing, said closure members having recesses therein, antifriction bearings mounted in said recesses and journalling said shaft, said bearings having inner and outer races, said outer races being in lateral contact with said cam members, said closure members being in lateral contact with said outer races, means for rigidly fixing one of said bearings on said shaft so that when said closure membars are secured to said casing said cam members are positively positioned through said outer races against said cylindrical member and, therefore, relative to each other, and said rotor is accurately positioned between said cam members, means for sealing between said closure members and said casing irrespective of their relative positions. passage means communicating the groove in said cylindrical member with spaced points on either side of said rotor, and other passage means in said cylindrical member communicating other 5 6' spaced points on either side or said rotor with Number Name Date said outlet port. 1,743,977 Petersen Jan. 14, 1930 WARREN R. TUCKER. 2,020,611 Knapp Nov. 12, 1935 ROBERT W. DIE'I'ERICH. 2,083,560 Grey et a1. June 15, 1937 5 2,154,457 Knapp Apr. 18, 1939 REFERENCES CITED 2,202,911 Johnson June 4, 1940 The following references are of rqcord m the 251138: Mann 1946 file or this patent: FOREIGN PATENTS UNITED STATES PATENTS 10 Number Country Date Number mm M 203,342 Great Britain Jan. 24, 1924 905,476 a 1 1908 503,742 Great Britain Apr. 13, 1939 1,236,399 Bowen Aug; 14, 1917 I 

